i have gas going into the oil - engine.

Asked by Mar 12, 2017 at 10:37 PM about the 1990 Ford Bronco II

Question type: Maintenance & Repair

what should I do when the fuel is getting into the engine. I need to correct this

2 Answers


Does it still have the MFI (MULTI FUEL INJECTION) 2.9l? MFI is the fuel route to the engine. If one or more Spark plugs do not fire (for any/all possible reasons) or one more injectors are not turning off or spraying correctly(may be sprinkling/dripping instead of fine mist. Basically fuel is going past the cylinder rings/seal into bottom end unburned.


Could need tune up, injectors cleaned (sticking), fuel regulator(#1 reason), Cracked heads, ECM, Crank & cam sensor send info to the ECM to control firing, those can be bad, Fuses, Shorts, systems designed to burn unburned fuel & vapors such as EGR, PCV, vacuum hoses. Is the motor cranking right up or are having to crank & crank on it to get it to run (flooding the engine)? Is it running rich? Is the oil just smelly like gas or what proof is there its fuel in oil? I agree that the engine could have issues with too high fuel pressure, or an injector sticking on, but have you done a compression test? It'd be good to know that you have a sound block and heads before you go any further. A cracked head might not show up in the coolant, but a comp test will show it. Bad rings will show up, too, and could be allowing gas to run into the oil. You also need to take a look at the PCV. If the engine is slugged up, this is the number one culprit. I've used B-12, Techron, but usually use Sea Foam in Brake booster vacuum line, fuel tank, added to oil or others like some BG44K. I think they all work more or less. Depends on how bad the injectors are clogged or corroded and if the oil has fried to the internals or not. Be sure to noticed if the fuel pump does not shut off when you turn the key on after 4-5 second prime & fuel pressure reached at FPR, if its just running & running then it is not build pressure (injector open or faulty FPR or relays are bad not turn pump off) Do fuel pressure test. Also the computer controls the fuel pump relay. Test with a known good ECM.

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